This is my favourite area of photography: catching the subject with a depth of field and creating a bokeh effect. I find the combination irresistable because the subject matter never fails to look beautiful regardless of what it is and at the same time the background also looks interesting. Bokeh can be smooth and silky or colourful and spotty - I'll take either of them any time. Using this 'method' celebrates the effect of light and works particularly well at night or low light. It always feel like I can create a form of magic with this effect.
Some of the images in nature also show a smooth bokeh effect where I have used a macro lens.